This program supports research that (a) identifies the major sources of difficulty that readers experience in comprehending written material; (b) develops assessments of reading comprehension that are sensitive to these comprehension difficulties and that can be used to inform instruction; and (c) identifies interventions in the form of approaches, programs, and materials that result in higher levels of reading comprehension. Through this program, the Institute will establish a scientific foundation for educational practice in reading comprehension that is likely to produce substantial gains in academic achievement.